Disgraced former Suffolk County Police Chief James Burke — who was denied bail on a misconduct case Friday — stymied the FBI’s investigation into the Gilgo Beach serial-killings for years, The Post has learned.

Burke — who was busted Wednesday for allegedly assaulting a Smithtown man in 2012 — refused to keep the feds in the loop on the unsolved murders of eight women, a man and a toddler on or near the beach, a source said.

That’s because he learned he was in the FBI’s cross hairs for assaulting Christopher Loeb, who allegedly stole his sex toys, sources said.

“Burke never wanted us involved in this [serial killer] case because he knew we were ­investigating him,” said a federal source.